//
//  Atom.h
//  FirstClass
//
//  Created by mac on 16-4-5.
//  Copyright (c) 2016年 liuchengming. All rights reserved.
//

#import <Foundation/Foundation.h>

@interface Atom : NSObject

@property(readonly) NSUInteger protons;
@property(readonly) NSUInteger neutrons;
@property(readonly) NSUInteger electrons;
@property(readonly) NSString *chemicalElement;

-(NSUInteger) massNumber;
@end
